Damping device for calculating machines



Feb. 18, 1958 w H 2,823,854

DAMPING DEVICE FOR CALCULATING MACHINES Fil ed Appil s, 1953 2 Sheets-Sheet 1 INVEIW'OP GEO/P65 v/71.77452,

Feb. 18, 1958 s. WALTHER 2,823,854 DAMPING DEVICE FOR CALCULATING MACHINES Filed April s. 1953 2 Sheets-Sheet 2 MIC-WIDE UFGE 44474 7715?;

United States Patent DAMPING DEVICE FOR CALCULATING MACHINES Georg Walther, Gerstetten, Wurttemberg, Germany; Maria Marthe Selma Hermine Walther and Hiidegard Helene Marianne Friedel Lina Erbe, both of Gerstetten, and Elisabeth Erika Anna Fahr, Gottmadingen, Germany, heirs of said Georg Walther, deceased Application April 3, 1953, Serial No. 346,772 Claims priority, application Germany April 4, 1952 4 Claims. (Cl. 23560) High speed calculating machines usually have the drawback that, in consequence of their high speed, the elements which move substantially in a straight line strike against each other and also against other parts of the machine. The invention especially intends to reduce the acceleration of the pin carriage of adding machines, so as to ease the impact of the pin carriage itself when it rebounds from its end position and one of its teeth is caught by a pawl, and, on the other hand, the impact of the restoring rod of the slide racks when they are returned from their adjusted position to their initial position, and strike against the pins of the pin carriage. The impact becomes especially severe both during the advance as well as during the return of the slide racks if the same figure is keyed in several place values. The projections on the slide racks of all keyed equal figures would then abut simultaneously against the pins during the forward movement, and these slides would be likewise engaged simultaneously by the restoring rod when returning them to their initial position.

For this purpose, according to the invention, the driving member for returning the pin carriage is designed so as to retard the inertia of the pin carriage when rebounding from its overtravel and to guide said pin carriage from a point in the vicinity of the first tooth to the supporting pawl which such tooth may then reach freely under the action of its spring.

A further striking action occurs in machines of this type when the restoring rod engages the slide racks, and especially when equal figures are set up in the pin carriage in several place values. Such striking action may be damped according to the invention if the restoring rod is made to engage these slides successively rather than simultaneously by shifting the restoring rod from its normal position perpendicular to the direction of movement of the slides to a different angular position relative thereto.

Such adjustment of the restoring rod may preferably be attained by designing the driving members which serve to rock the restoring rod so as to advance the opposite ends thereof non-uniformly. If, for example, a cam drive is used, the opposite ends of the restoring rod may be actuated by cams of different shape so that, in its end positions, it lies rectangularly to the slide racks, while during its movement it is placed at an angle deviating from one of 90 relative to the slides to a position obliquely to the direction of movement.

In the drawing, an embodiment of the damping device according to the invention is illustrated by way of example.

Fig. 1 shows the pin carriage and its drive in a perspective view;

Fig. 2 is a side view of the pin carriage shown in Fig. 1, seen in the direction of the arrow A;

Fig. 3 is a side view similar to Fig. 2, but shows the parts in another position;

Fig. 4 is a side view of a slide rack and the restoring mechanism therefor; while Fig.5 isaplan view of Fig. 4.

The pin carriage 1 may slide in a longitudinal direction on rods 2 mounted on a stationary plate 2a and is moved in the direction of the arrow a by a spring 3. This movement is stopped by a pawl 4 adapted to engage each of the teeth 5. The pawl may be released if one of the keys (not shown), each corresponding to a certain figure, is struck so that the pin carriage 1 may move under the action of the spring 3 from one tooth S to the neXt one. The corresponding pin 6 is displaced by the key in a known manner. A crank lever 7 which is pivotally supported on a stationary bolt 8 is pivotally connected with a link 23 pivoted to the pin carriage 1. A rod 9, con nected with the opposite end of the lever 7 by a pivot 9a is adapted to engage a lever 12 pivotally supported by a bolt 10 and provided with a roller 11. The roller 11 engages a cam 13 fastened on, and rotating with, the main shaft 14. A spring 11a keeps the roller 11 in engagement with the cam. If by the release of the pawl 4 the pin carriage 1 is moved, for example, from its initial position shown in Fig. l in full lines to the position in which the lever 7 is in the position indicated by dot-anddash lines, the cam 13 will return the pin carriage into the initial position by means of the lever 12, the rod 9, and the crank lever '7 against the pull of the spring 3. Such movement also causes a yielding buffer 15, inserted between the pin carriage and the stationary plate 2a, and consisting e. g. of rubber, to be compressed to such an extent that the first of the teeth 5 contacts the engaging surface of the pawl 4 and travels a certain distance b beyond such surface. This movement insures the return of all pins 6 to their initial position by means of an abutment 24- which presses them upwardly in a known manner.

in consequence of the springy effect of the butter 15 and the pull of the spring 3, the pin carriage 1 tends to jump forwardly from the position shown in Fig. 3 against the first tooth 5 and to produce a blow which could impair the machine and especially the relatively weak tooth if such blow were not caught or softened. For this purpose, the cam disk 13 is so devised that, after the roller 11 on the lever 12 has reached the highest point of the cam 13 designated by the reference numeral 16, and while the roller 11 runs down over a slightly sloping portion 17 of the cam, the lever 12 may at first rock only so far that the first tooth 5 does not fully reach the pawl 4, so that the rebounding force of the pin carriage will be caught by the cam disk 13 until the roller 11 runs over the steeply sloping portion of the cam and thereby allows the first tooth 5 to engage the supporting pawl 4. Even though the pin carriage 1 moves at a high speed, a strong blow of the first tooth 5 against the supporting pawl 4 is thus avoided, resulting in a noiseless operation of the machine and preventing a premature damage of the tooth.

A further blow occurs in the known machines during the advance and return of the racks 18a (Fig. 4) which actuate the accumulator, when these racks move against the pins 6 of the pin carriage 1 under the action of a spring in the direction indicated in Fig. 1 by the arrow A or are returned by the restoring rod 20 to their initial position againts the action of the spring 19. The blow is especially severe it a plurality of equal figures are keyed in different decimal places, since the projections on the slides 18 which are associated with said racks will then strike against the pins 6 simultaneously or the slides 18 will ail be engaged at the same time by the restoring rod during the return movement. For distributing and softening such blow, the two cams 22, which actuate the levers 22 carrying the restoring rod 20, have such different curvature that the levers are synchronously actuated so as to move the restoring rod 20 to an oblique position relative to a series of pins 6 of equal figure value but dilterent decimal or place value, as indicated in Fig. 5 in dot-aud-dash lines. Therefore, the projections of 3 the slides 13 do not engage the pins 6 simultaneously even if equal figures in several places are keyed, and these slides are likewise not engaged simultaneously by the restoring rod 20 when they are returned to their initial position. Thus, if the same figure or number is keyed in a plurality of pins 6, no severe blow can occur either during the advance or the return movement, since these pins are then engaged one after the other, while the slides are likewise not engaged simultaneously but successively by the restoring rod 20.

What I claim is:

1. In a calculating machine comprising, in combination with a pin carriage, series of pins provided in said carriage and being adapted to be adjusted into an operative position, racks for actuating an accumulator of the machine, feelers associated with said racks, means for bringing said feelers into engagement with the adjusted pins, and a restoring rod returning said feelers into their initial position; and means advancing the opposite ends of said restoring rod non-uniformly when returning said feelers so as to place said rod at an angle relative to a vertical plane passing through at least two of said pins of equal figure value but different place values.

2. In a calculating machine comprising, in combination with a pin carriage, series of pins provided in said carriage and being adapted to be adjusted into an operative position, racks for actuating an accumulator of the machine, feelers associated with said racks, means for bringing said feelers into engagement with the adjusted pins and a restoring rod returning said feelers into their initial position; rocking levers carrying the opposite ends of said restoring rod, cams of different shape actuating said rocking levers non-uniformly thereby advancing the opposite ends of said restoring rod non-uniformly when returning said feelers so as to place said rod at an oblique angle relative to a vertical plane passing through at least two of said pins of equal figure value but diflierent place values, and means for driving said earns.

3. In a calculating machine comprising, in combination with a pin carriage, series of pins provided in said carriage and being adapted to be adjusted into an operative position, teeth provided on said pin carriage, a stationary pawl, and means for bringing one of said teeth into engagement with said pawl; means returning the said pin carriage somewhat farther than into the position of rest and guiding it from this position positively but gradually and without shock into engagement with the first tooth of said pin carriage, resilient means for cushioning the pin carriage at the farthest end of its returning movement and for then assisting in the return of the carriage to its normal position of rest, and means for automatically restoring said pins to the inoperative position during such returning movement.

4. In a calculating machine comprising, in combination with a pin carriage, series of pins provided in said carriage and being adapted to be adjusted into an operative position, teeth provided on said pin carriage, a stationary pawl, and means for bringing one of said teeth into engagement with said pawl; means comprising a cam returning the said pin carriage somewhat farther than into the position of rest, the cam being shaped so as to guide said pin carriage positively from this position but gradually and without shock into engagement with the first tooth of said pin carriage and to reduce the acceleration of the pin box before the pin of said pin carriage reaches said pawl, resilient means for cushioning the pin carriage at the farthest end of its returning movement and for then assisting in the return of the carriage to its normal position of rest, and means for automatically restoring said pins to the inoperative position during such returning movement.

References Cited in the file of this patent UNITED STATES PATENTS 1,957,617 Siewert May 8, 1934 2,203,533 Landsiedel June 4, 1940 2,229,980 Landsiedel Jan. 28, 1941 2,247,938 Bower July 1, 1941 2,303,692 Hellgren Dec. 1, 1942 2,342,529 Chase Feb. 22, 1944 

